<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div {
            width: 300px;
            height: 300px;
            background: red;
            position: absolute;
            top: 50%;
            left: 50%;
            margin-left: -150px;
            margin-top: -150px;
            border-radius: 50%;
            animation: play 1s linear infinite alternate;
        }
        
        @keyframes play {
            0% {
                /* box-shadow: 0px 0px 0px 0px red; */
            }
            100% {
                box-shadow: 0px 0px 100px 10px gold;
                background: gold;
            }
        }
    </style>
</head>

<body>
    <div>
    </div>
</body>

</html>